Bifurcation analysis of a hovering helicopter with slung load non-linear dynamics

• Autorzy: Sibilski K.

Warianty tytułu

PL

Bifurkacyjna analiza nieliniowej dynamiki śmigłowca z podwieszonym ładunkiem w zawisie

• Konferencja: Krajowe Forum Wiropłatowe (4 ; 19-20.10.2001 ; Warszawa, Polska)
• Języki publikacji: EN

Abstrakty

EN

Application of helicopters to transport of heavy and bulky loads creates the stability problems specially of hovering with hanging loads. The presence of an external load modify the flight dynamics and handling qualities characteristics of a helicopter because the load behaves like a pendulum, and it can change natural frequencies and mode shapes of the low frequency modes of the helicopter. Additionally, the aerodynamic characteristics of the load may make it unstable in certain flight conditions, with obvious repercussions on the stability and the safety of the entire helicopter/load system. The paper presents a study of the fight dynamics of an articulated rotor helicopter carrying a suspended load. The load is modelled as pendulum with a single suspension point. Helicopter with suspended load is the inherently non-linear and lime varying system. Dynamical systems theory provides a methodology for studying non-linear systems of ordinary differential equations. Bifurcation theory is a part of that theory which is considering changes in the stability lead to qualitatively different responses of the system. Results from dynamical systems theory were used to predict the nature of the instabilities caused by bifurcations.

PL

Zastosowanie śmigłowców do prac dźwigowych stwarza potrzebę zbadania stateczności ruchu układu śmigłowiec-podwieszony ładunek. Obecność zewnętrznego podwieszenia zmiania charakterystyki dynamiczne śmigłowca i jego osiągi. Poruszający się jak wahadło ładunek wpływa w istotny sposób na częstości i postacie ruchów własnych śmigłowca. Ponadto obciążenia aerodynamiczne ładunku mogą przyczyniać się do destabilizacji układu w szerokim zakresie parametrów eksploatacyjnych, wpływając w istotny sposób na bezpieczeństwo lotu śmigłowca. W pracy przedstawiono nieliniowy model dynamiki układu śmigłowiec-podwieszony ładunek (ładunek modelowany jest jako przestrzenne wahadło fizyczne). Klasyczne metody badania stateczności ruchu, w przypadku tak silnie nieliniowych układów równań różniczkowych zawodzą. Dlatego ruch śmigłowca z podwieszonym ładunkiem badano stosując metody Teorii Systemów Dynamicznych i Teorii Bifurkacji. Zaprezentowano wyniki bifurkacyjnej analizy dynamiki układu śmigłowiec-podwieszony ładunek w zawisie. Przeanalizowano wpływ długości liny i masy ładunku na stateczność położeń równowagi. Przebadano występujące bifurkacje i przedstawiono zakresy położeń niestatecznych.

Słowa kluczowe

EN

helicopters; stability testing

PL

śmigłowiec; badanie stateczności ruchu

• Wydawca: Wydawnictwa Naukowe Instytutu Lotnictwa
• Czasopismo: Prace Instytutu Lotnictwa
• Rocznik: 2002
• Tom: z. 1-2 (168-169)
• Strony: 43--50
• Opis fizyczny: Bibliogr. 41 poz., rys., wykr.

Twórcy

autor

Sibilski K.

• Radom University of Technology

Bibliografia

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